Source: Julie Weed - N.Y. Times ( Paid Registration )

The airlines’ most valuable customers, those who fly most often and spend the most money, receive the sorts of benefits that most travelers can only salivate over — lounge access, free checked luggage, free upgrades, free itinerary changes. But most travelers aren’t constantly flying, and they will find that the airlines have made it a lot more complicated to qualify even for a piece of that good life.

Read Full Article: You practically need a Ph.D. to figure out frequent-flier status